What Is a CFM File?

Cold Fusion Markup files support the ColdFusion web server

Screenshot of several CFM files in Windows 10 that open with Notepad

A file with the CFM file extension is a Cold Fusion Markup file. They're sometimes called Cold Fusion Markup Language files, which might be seen abbreviated as CFML.

Cold Fusion Markup files are web pages made up of specific code that enables scripts and applications to run on a ColdFusion web server.

How to Open a CFM File

CFM files are text-based, which means they can be opened as a text file with any text editor, like Notepad in Windows or Brackets. Programs like these will properly show the contents of the file.

Other programs can open CFM files too, like Adobe's ColdFusion and Dreamweaver software, as well as New Atlanta's BlueDragon.

Chances are, however, that unless you're a web developer, a CFM file you encounter probably shouldn't have been presented to you in that way. In other words, a server somewhere incorrectly provided you with a CFM file instead of the usable file that you expected.

For example, if you downloaded a CFM file from somewhere that you expected to be in a format like PDF or DOCX, Adobe Reader isn't going to open the CFM and show your bank statement, nor is Microsoft Word going to show you that free greeting card template when it ends in CFM.

In these cases, try renaming the file, replacing the .cfm portion with .xyz, where "xyz" is the format you expected—such as .pdf or .docx. Then try opening the file normally, as you originally planned.

How to Convert a CFM File

Considering the text-based nature of a CFM file, there's little reason to use a conversion program. However, a CFM file can be saved or converted to HTM/HTML to be viewable in a browser, but any functionality provided by the ColdFusion server would, of course, be lost.

Most CFM files you'll see supposed to end in .cfm. The easiest way to convert the file will be by attempting to renaming the file instead of converting it in the usual sense.